Quantitative Morphological Characters Research Articles

Trophic morphology features allow Astyanax endemic species coexistence in a Neotropical river system.

Resource partitioning has an essential role in interspecific relations, especially in congener species, which share many morphological traits. In some places, small characids coexist through resource partitioning, which may reduce their interspecific competition. Astyanax species (e.g., Astyanax minor, Astyanax gymnodontus and Astyanax bifasciatus), for example, coexist in different water bodies from the Iguaçu River basin. These species have high phenotypic plasticity and many morphologic specializations that allow them to live in different habitats. Based on evidences that these species modified their feeding habits because of changes in resource availability in Iguaçu River, this study tested two hypotheses: (a) there are differences in head morphology, number of teeth and number of gill rakers among the species of Astyanax; and (b) there are differences in gill arch and gill raker morphology among the species of Astyanax, which may favour their trophic resource partitioning in Iguaçu River. The head morphological traits and quantitative morphological characters were summarized in a principal coordinates analysis (PCoA), and the analysis of similarities (ANOSIM) showed significant differences among species. Gill morphological measurements were analysed through analysis of covariance (ANCOVA), and it also showed significant differences in gill arch and gill raker morphology among species. Therefore, the analysis of ecomorphological traits related to trophic habits revealed some differences that may suggest a tendency of reducing competition for trophic resources in the Iguaçu River basin.

Morphologic and Chemotaxonomic Studies of Some Teucrium L. (Lamiaceae) in Zagros Region, Iran

The genus Teucrium L. is a well-known medicinal plant belonging to Lamiaceae family and Ajugoideae subfamily. The present study aims to evaluate the taxonomic status of the Teucrium species using both morphological and flavonoid characteristics and to determine the flavonoid classes. A total of 64 accessions belonged to eight species, and five subspecies were collected from different Zagros regions, Iran. Twenty-nine quantitative and qualitative morphological characters were studied. Extraction of leaf flavonoid was accomplished using a rotary evaporator and MeOH 90%. Identification of the chemotaxonomic position and flavonoid class of Teucrium species was investigated by thin layer chromatography, column chromatography and High Performance Liquid Chromatography-Micromass Quattro micro Atmospheric Pressure Ionization Mass Spectrometer. All information was analyzed using NTSYS pc. 2, PAST v.3.18 and Cluster Vis v. 1.8.2. According to the findings, T. polium accessions significantly revealed the highest value of morphological and flavonoid variations. All subspecies of T. orientale were definitely separated, but some relationships were observed between its subspecies, including taylori and glabrescens. All members of two sections of Polium and Teucris were definitely recognized. A total of seven flavonoid classes were determined from which the highest amounts of abundance were attributed to flavones (18) and isoflavones (17). In conclusion, morphological and flavonoid markers were introduced as appropriate characteristics in the taxonomic relationships of Teucrium species. All the evidence of the present research was first described for Iran.

A procedure for taxon assessment based on morphological variation in European water frogs (Pelophylax esculentus complex)

Methods for morphological identification of water frogs from the Pelophylax esculentus complex have changed over the decades. Still, without resort to genetic analyses, water frogs remain among the most difficult European amphibians to distinguish due to their hybrid nature. The aim of this study was to identify a reliable set of quantitative and qualitative morphological characters that objectively resolve species? identification in the Pelophylax esculentus complex and provide a rapid and robust procedure for taxon identification. Our results showed a substantial difference in morphological characteristics among taxa. The shape and size of the metatarsal tubercle along with the coloration of the hind limbs and flanks appear to be the most important diagnostic traits. Linear discriminant analysis with both quantitative and qualitative traits as a rapid method for the assessment of water frog taxa showed satisfactory accuracy and prediction classification for all 3 members of the complex.

Morphologic and genetic analysis for geographic populations of greenbug Schizaphis graminum (Hemiptera: Aphididae) in Egypt

Greenbug Schizaphis graminum is one of widespread aphid species in most wheat growing regions of Egypt that causes severe damages to crops. Studying morphological and genetic variations within insect pest populations are essential for identifying species and population distinctions and subsequently developing integrated pest management. Sixteen geographic populations of S. graminum were sampled from wheat fields in Egypt. Specimens were characterized by morphological screening for 19 quantitative morphological characters, examination of genomic DNA polymorphism with 11 inter simple sequence repeats (ISSR) primers, and measuring melting temperature (Tm) for cDNA of the mitochondrial cytochrome oxidase subunit I (COI) gene. The greatest morphological variance was observed among aphid populations from Domiata, El-Menia, and Beni-Suif. Geographic location of sampled populations had significant effect on melting temperature of the COI gene. The highest value was observed in populations from Assuit and the lowest from El-Gharbia. Populations from El-Monofia and Kafer El-Shikh were most similar based a combination of COI melting temperatures and quantitative morphological features. Tested ISSR primers showed a polymorphism rate of 49.43% among geotypes. The UBC814 primer recognized a population-specific band of 950 bp that characterized the Domiata population. Moreover, UBC811 and UBC868 primers generated bands with molecular sizes 440 and 340 bp characterizing only populations of Lower and Upper Egypt, respectively. ISSR analysis revealed that geographic populations from El-Behera, Domiata, and Kafer El-Shikh are genetically homologous with identities of 90.4–90.7%. In contrast, populations of Luxor and El-Behera are genetically analogous. Finally, a molecular branching key was constructed to discriminate among tested populations.

Pollen diversity in the genus Carlina L. (subtribe Carlininae, Compositae) and its systematic significance

Pollen morphology of 19 species, 4 subspecies, and 1 variety of Carlina was studied in detail by light and scanning electron microscopy. Qualitative and quantitative pollen morphological characters which vary between taxa are found in the length of the ectocolpi, presence/nature of the echinae, pollen size and shape, lumina area, P/E ratio, polar axis, equatorial diameter, pollen shape, ectocolpi length, sculpture of ectoaperture membranes, area of lumina, and exine ornamentation. Three main pollen types are discerned: the C. atlantica type characterized by P/E ≤ 1.00, the C. curetum type characterized by P/E = 1.03–1.11, and the C. acanthifolia type with ratio P/E = 1.24–1.50. HCA and PCA analyses were carried out to detect the potential palynological characters which could be used to identify taxa. The data suggest that several pollen morphological characters can be used to delimit the taxa of Carlina. Dichotomous artificial keys based on palynological data are also given.

Phylogeographic and taxonomic considerations on Goniolimon tataricum (Plumbaginaceae) and its relatives from south-eastern Europe and the Apennine Peninsula

Goniolimon species are mainly components of the Eurasian steppe or steppe-like rocky vegetation, with some taxa occurring also in south-eastern Europe and northern Africa. We analysed the variability of: (i) two maternally inherited plastid loci (rpl32-trnL and 3′rps16-5′trnK) in 110 individuals of six currently accepted species from the Balkans and one species from the Apennines, to provide new insights into their origin and evolutionary history; and (ii) quantitative morphological characters (14 independent characters and one ratio character) in 641 individuals of three species of which two are morphologically and ecologically similar (G. italicum and G. tataricum) and the third, G. dalmaticum, was frequently misidentified as G. tataricum in the past, to provide new taxonomic treatment for proposed G. tataricum subspecies. We delineated several quantitative and five qualitative characters studied in a more limited sample as diagnostic for the identification of four subspecies (three newly described and one in a new rank) of G. tataricum. The history of westward peripheral populations of this species in the Balkans and the Apennines was rather complex and driven by local geo-historic events. These events facilitated multiple waves of east–west expansion of lineages originating from sources outside of the Balkan Peninsula which periodically diversified and occupied localised areas in the Balkans during the Pleistocene. An initial spread of an ancient G. tataricum lineage throughout south-eastern Europe probably occurred during the Messinian Salinity Crisis. Inter- and intraspecific hybridisation/introgression, as well as retention of ancestral polymorphisms, was common in G. tataricum and related taxa over time.

Pollen morphological traits analysis of eighteen 'Nepeta' species in Iran

Nepeta is one of the largest genera of Lamiaceae, which is widely distributed in Iran. Several species of the genus are traditionally used as culinary, industrial, and medicinal plants. In the present study, we examined fourteen qualitative and quantitative pollen morphological characters of twenty-four populations of eighteen Nepeta using light and scanning electron microscope. The pollen grains are radially symmetric, isopolar, and hexacolpate in all species. We have found that the quantitative features vary among the studied taxa. According to PCA analysis, the colpus length and width are the most variable traits. Polar view shapes in all the studied taxa are circular, while the equatorial view is prolate-spheroidal, subprolate, perprolate, and prolate. We determined microreticulate and bireticulate exine sculpturing, and the bireticulate type was dominant. We revealed that polar and equatorial axes length of pollen grains varied between populations of the same species, and they, therefore, should be ignored in taxonomical identification of species. The polar view was similar in all the studied pollen grains and could not be considered as a diagnostic trait. The equatorial shape was stable between populations of the same species, and this was taxonomically important, while we registered some infraspecific variations in exine sculpture. Our cluster of taxa based on the pollen morphology is not in concordance with the traditional sectional classification of the genus.

Patterns of development of advanced clonal apple rootstocks of the Michurinsk State Agrarian University selection in the mother plantation

This paper reveals main patterns of development of advanced clonal apple rootstocks of the Michurinsk State Agrarian University selection in the mother plantation. The studied growth and development indicators of shoots, as well as the level of their rooting in 40 genotypes, demonstrate significant heterogeneity of hybrid plants, which is due to their different genetic origin and the associated unequal growth force of parent shrubs. Correlations between the main quantitative morphological characters of parent shrubs of the studied genotypes were revealed. An interrelation of the height of the parent shrub and the area of its leaf surface is noted - on the expectation of 0.71 shoot; for the entire uterine shrub – of 0.45; between the output of standard layering from the shrub and the average rooting score (at 0.72). Promising clonal rootstocks with high yield indices in the mother plantation have been identified.

Reconstructing the archosaur radiation using a Middle Triassic archosauriform tooth assemblage from Tanzania.

Following the Permo–Triassic mass extinction, Archosauriformes—the clade that includes crocodylians, birds, and their extinct relatives outside crown Archosauria—rapidly diversified into many distinct lineages, became distributed globally, and, by the Late Triassic, filled a wide array of resource zones. Current scenarios of archosauriform evolution are ambiguous with respect to whether their taxonomic diversification in the Early–Middle Triassic coincided with the initial evolution of dietary specializations that were present by the Late Triassic or if their ecological disparity arose sometime after lineage diversification. Late Triassic archosauriform dietary specialization is recorded by morphological divergence from the plesiomorphic archosauriform tooth condition (laterally-compressed crowns with serrated carinae and a generally triangular lateral profile). Unfortunately, the roots of this diversification are poorly documented, with few known Early­–Middle Triassic tooth assemblages, limiting characterizations of morphological diversity during this critical, early period in archosaur evolution. Recent fieldwork (2007–2017) in the Middle Triassic Manda Beds of the Ruhuhu Basin, Tanzania, recovered a tooth assemblage that provides a window into this poorly sampled interval. To investigate the taxonomic composition of that collection, we built a dataset of continuous quantitative and discrete morphological characters based on in situ teeth of known taxonomic status (e.g., Nundasuchus, Parringtonia: N = 65) and a sample of isolated teeth (N = 31). Using crown heights from known taxa to predict tooth base ratio (= base length/width), we created a quantitative morphospace for the tooth assemblage. The majority of isolated, unassigned teeth fall within a region of morphospace shared by several taxa from the Manda Beds (e.g., Nundasuchus, Parringtonia); two isolated teeth fall exclusively within a “Pallisteria” morphospace. A non-metric multidimensional scaling ordination (N = 67) of 11 binary characters reduced overlap between species. The majority of the isolated teeth from the Manda assemblage fall within the Nundasuchus morphospace. This indicates these teeth are plesiomorphic for archosauriforms as Nundasuchus exhibits the predicted plesiomorphic condition of archosauriform teeth. Our model shows that the conservative tooth morphologies of archosauriforms can be differentiated and assigned to species and/or genus, rendering the model useful for identifying isolated teeth. The large overlap in tooth shape among the species present and their overall similarity indicates that dietary specialization lagged behind species diversification in archosauriforms from the Manda Beds, a pattern predicted by Simpson’s “adaptive zones” model. Although applied to a single geographic region, our methods offer a promising means to reconstruct ecological radiations and are readily transferable across a broad range of vertebrate taxa throughout Earth history.

Cryptic Species Discrimination in Western Pine Beetle, Dendroctonus brevicomis LeConte (Curculionidae: Scolytinae), Based on Morphological Characters and Geometric Morphometrics.

The western pine beetle (WPB), Dendroctonus brevicomis LeConte, is a major mortality agent of pines in North America. A total of 706 adults of WPB from 81 geographical sites were analyzed with traditional and geometric morphometric methods to evaluate the variation of discrete and quantitative morphological characters with particular attention to the antenna, spermatheca, and seminal rod. Principal coordinates and canonical variate analyses supported three geographical groups in WPB: (1) West, from British Columbia to southern California along the Pacific coast, Idaho, and Montana; (2) East-SMOC, including Nevada, Utah, Colorado, Arizona, New Mexico, Texas, Chihuahua, and Durango; and (3) SMOR, including Coahuila, Nuevo Leon, and Tamaulipas. The pubescence length on the elytral declivity was a robust character for separating West specimens from the other groups. Additionally, the genitalia shape both female and male in dorsal view was a reliable character for discriminating among groups. Based on these results, which agree with genetic and chemical ecology evidence, we herein reinstate Dendroctonus barberi Hopkins (East-SMOC group) and remove it from synonymy with D. brevicomis (West group). Differences in the spermatheca and seminal rod shape of SMOR specimens suggest that these populations might be a different species from D. barberi and D. brevicomis.

Morphology and isozyme variation among madeira vine (Anredera cordifolia) accessions from southeastern part of Central Java, Indonesia

Abstract. Restykania, Suratman, Pitoyo A, Suranto. 2019. Morphology and isozyme variation among madeira vine (Anredera cordifolia) accessions from southeastern part of Central Java, Indonesia. Biodiversitas 20: 3024-3032. The genetic diversity among madeira vine accessions from southeastern part of Central Java has not been investigated in detail. Information on genetic diversity and relationship among accessions of this plant will provide important input into determining resourceful management strategies and guiding the improvement of plants through plant breeding programs. The objective of this study was to evaluate variation of morphology and isozyme among madeira vine (Anredera cordifolia (Ten.) Steenis) accessions from southeastern part of Central Java. A total of 13 madeira vine accessions were used for morphological observations and isozyme analysis. Morphological diversity was characterized based on measurements and observations of vegetative structures such as stems, leaves, and aerial tubers. Identification of biochemical markers was done using peroxidase and esterase isozyme systems. A relationship dendrogram among accessions was constructed based on the genetic similarity matrix by applying a cluster analysis. The analysis of quantitative and qualitative morphological characters revealed that the majority of the tested traits showed variation, indicating that there was variability among the tested madeira vine accessions. Polymorphism was observed using isozyme of peroxidase (i.e. two banding patterns) and esterase (i.e. five banding patterns). Based on the dendrogram at a level of 63 % similarity, it showed distinct separation of 13 madeira vine accessions into two major clusters. Cluster I consisted of nine accessions and the closest relationship was shown between KLT 3 and KLT 1 accessions that had 94 % of similarity coefficient. The remaining four accessions were clustered separately as Cluster II with similarity coefficient of 73 %. Therefore, genetic characterization based on morphological and isozyme markers obtained in this study is valuable to understand genetic variability and relationship among madeira vine accessions in southeastern part of Central Java.

Variability of Catharanthus roseus based on morphological and anatomical characters, and chlorophyll contents

Abstract. Samiyarsih S, Naipospos N, Palupi D. 2019. Variability of Catharanthus roseus based on morphological and anatomical characters, and chlorophyll contents. Biodiversitas 20: 2986-2993. Catharanthus roseus (L.) is an important medicinal plant of the family Apocynaceae used to treat many of the diseases. C. roseus also possess good antioxidant potential. The purpose of this research was 1) to determine the variability of C. roseus based on the morphological, anatomical characters and chlorophyll contents, 2) to know the differences in morphological, anatomical characteristics and chlorophyll contents of C. roseus found in Banyumas Regency. The research used a survey method, with a purposive sampling technique. Preparation of leaf for anatomical analysis was based on paraffin method. The results showed that C. roseus in Banyumas Regency were grouped into eight varieties. The morphological characters observed consisted of 21 characters, 8 quantitative characters, and 13 qualitative characters. Most of the quantitative morphological and anatomical characters were significantly diverse (p <0.05) except for petiole length, corolla number, stomata width and number of trichomata. The eight varieties of C. roseus have different chlorophyll a, chlorophyll b, and total chlorophyll contents but their anthocyanin contents were not significantly different.

P>Taxonomic revision of the Colombian Tityus (Archaeotityus) (Scorpiones, Buthidae) species: a morphological and morphometric approach, with a description of a new species.

We present a taxonomic revision of the Colombian Tityus (Archaeotityus) species based on morphological and morphometric evidence. We examined more than 385 specimens and evaluated new and previously used qualitative and quantitative morphological characters. We redescribe the Colombian species and present morphological characters for both sexes and an emended diagnosis for the subgenus Tityus (Archaeotityus). We describe a new species Tityus guane sp. nov. from Santander department, Colombia, Tityus betschi Lourenço 1992 is synonymized with Tityus parvulus Kraepelin, 1914, and Tityus wayuu Rojas-Runjaic Armas, 2007 is synonymized with Tityus tayrona Lourenço, 1991. We measured 186 specimens and performed a multivariate principal component analysis (PCA) for 34 selected morphometric ratios for each sex. We found that a few morphological ratios support species level distinctions within the Colombian species. We provide updated distributional maps with new records and an identification key for both sexes. Furthermore, we provide an updated checklist for the subgenus and a discussion about the character systems used within Tityus (Archaeotityus). The new morphological characters proposed and the traditional morphometry examined with a PCA are useful for studying Tityus (Archaeotityus) taxonomy.

Morphological and essential oil variations among Iranian populations of Salvia chloroleuca (Lamiaceae)

Salvia chloroleuca Rech. f. & Aell. is one of the perennial species of the Lamiaceae family in Iran, which has antimicrobial and antitumoural properties. In the current research, the morphological variables and hydrodistilled essential oils of two populations, from Polor and Neyshabur, of this species were evaluated. We studied 10 and 40 individuals for morphometrics and essential oils, respectively. Morphological data were analyzed using SPSS. Furthermore, the extracted oils were analysed using GC and GC/MS. The qualitative morphological characteristics were stable between the populations, while the quantitative ones highly varied. The one-sample variance test revealed significant differences for most of the studied features. The yielded oil highly differed between these populations. The first and second main groups of compounds were the same for both populations, but with different percentages. However, the third and fourth main groups of compounds were not similar. Furthermore, the main compounds of essential oil differed between the studied populations. The major compounds of the Polor population were: β-pinene (22.7%), α-pinene (18.3%), germacrene D (7.7%) and sabinene (6.6%). However, spathulenol (19.8%), bicyclogermacrene (11.4%), p-cymene (10.8%) and β-pinene (10.4%) constituted the major compounds of the Nyshabur population. In total, the Neyshabur population had higher amounts of sesquiterpene and oxygenated compounds than the other population. The results indicated that in this species the quantitative morphological characters and essential oils were strongly affected by environmental factors.

Batillipes pennaki Marcus, 1946 (Arthrotardigrada: Batillipedidae): deciphering a species complex.

Batillipes pennaki has been considered a common and a cosmopolitan marine tardigrade species. However, the original diagnosis of this species is very incomplete, and consequently there is a high probability of incorrect records. Therefore, a comparative analysis of quantitative and qualitative morphological characters among eight different populations from the Atlantic basin was done in this study to investigate if B. pennaki is a complex of similar species, each with a restricted distribution range. The result of discriminant analyses showed clear morphometric differences between populations that were arranged into three main groups, distinguishing Western Atlantic populations, Eastern Atlantic populations and a Mediterranean population. Furthermore, the result of analyses of morphological structures revealed peculiarities of some traits with taxonomic relevance, such as leg IV sensory organs and primary clavae, consistent with the clusters revealed by quantitative data, allowing us to distinguish three different pseudocryptic species and supporting the hypothesis that B. pennaki is a species complex.

The Variability of Crossbreed-cashew Accession Numbers at Two Years Age Based on Morphological Characters

<em>Cashew in cross-pollinated plants, one effort to improve the diversity gentik in germplasm of cashew nut was carried out by a cross between high-producing elders  and the elderly tolerant of </em>helopeltis sp.<em> </em><em>The aimed of this study is to know the variability of 25 accession of cashew nut hybrid based on leaf morphology characters. The study was conducted at Cikampek Experimental Station, from January to December 2016, using direct observation method <strong> </strong>the<strong> </strong>qualitative and quantitative morphological characters of the cashew at the age of two years. Observations were done on eight plants per plot, each observed as many as 50 leaves per plant. The result showed that the morphology character of cashew nut varied. Character of leaf ovatus, obovatus, and oblong The trunk and rounded ends, pointed and blunt. Form the edge of the leaf, form the bottom and top surfaces smooth leaves. The color of the adult leaves was dark green, and young leaves were reddish brown and  yellowish  green.  The  diversity  18.35-100 %  and  the level the closeness of 0.10-0.38, divided into two groups. Group one separated by characters a leaf shape  oblongus,  leaf  base  form  of the rotundatus, leaf tip shape rotundatus and obtusus and young leaves color BGB N199 A, group two separated by the <em>characters of the leaf shape obovate, leaf base form of the obtusus, leaf tip shape acuminatus and retusus and young leaves color GB 200 B. The lenght of the leaf characters, the width of the leaf, the leaf thickness and the length of the petiole vary with the degree of diversity 47.67-96.94 % and the proximity distance 0.19-6.19 which is divided into teo groups. One group was separated by the the highest leaf length character 17.6-20.6 cm, whereas the two group was separated by the smallest leaf length character 14.6-17.1 cm.</em></em>

Genetic Stability of Banana Plant Regenerated from Floral Axis Organogenesis Assessed by Newly Developed SSR Markers

Molecular marker is robust to precisely monitor the genetic stability of in vitro -banana plants. This study examined the genetic stability of 8 monthold banana plants of Soka variety derived from floral axis organogenesis using newly developed SSR markers. The results showed that the same qualitative and similar quantitative morphological characters of pseudostem, leaf and fruit were identified between mother plants and culture plants from floral axis regeneration. Both plants types were quite similar in number of tillers, brix percentage, fruit peel/mesocarp thickness and fruit length. Eleven out of 211 good quality of SSR loci showing high homology with important genes were selected for suitable PCR primers and produced unambiguous bands.The number of total bands was 323 for total SSR primers, in range of 20-60 per primer for total individual plants. Most culture plants showed identical with their mother plants, with very minor variation as reflected by genetic similarity coefficient range of 0.9-1.0. A high similar pattern on SSR to support morphological characters of mother plants and culture plants indicated a successful micropropagation using floral axis to encounter off-type clones.The floral axis organogenesis in this study is able to provide sufficient genetic materials of Soka for varietal registration and other applications.

Bayesian Estimation of Species Divergence Times Using Correlated Quantitative Characters.

Discrete morphological data have been widely used to study species evolution, but the use of quantitative (or continuous) morphological characters is less common. Here, we implement a Bayesian method to estimate species divergence times using quantitative characters. Quantitative character evolution is modeled using Brownian diffusion with character correlation and character variation within populations. Through simulations, we demonstrate that ignoring the population variation (or population "noise") and the correlation among characters leads to biased estimates of divergence times and rate, especially if the correlation and population noise are high. We apply our new method to the analysis of quantitative characters (cranium landmarks) and molecular data from carnivoran mammals. Our results show that time estimates are affected by whether the correlations and population noise are accounted for or ignored in the analysis. The estimates are also affected by the type of data analyzed, with analyses of morphological characters only, molecular data only, or a combination of both; showing noticeable differences among the time estimates. Rate variation of morphological characters among the carnivoran species appears to be very high, with Bayesian model selection indicating that the independent-rates model fits the morphological data better than the autocorrelated-rates model. We suggest that using morphological continuous characters, together with molecular data, can bring a new perspective to the study of species evolution. Our new model is implemented in the MCMCtree computer program for Bayesian inference of divergence times.

New record of Trichodina unionis (Ciliophora, Trichodinidae) from freshwater gastropods in Bangkok, Thailand.

Trichodinids, which are ciliate protists, are causative agents of an aquatic animal disease, trichodiniasis, especially among both captive and wild fish. This disease can adversely affect aquaculture and have economic impacts. The objectives of this study were to evaluate the prevalence and mean intensity of Trichodina unionis infection, describe qualitative and quantitative morphological characters, and perform a molecular phylogenetic analysis. The gastropod samples were randomly collected by hand-picking and a hand net. Trichodina unionis was collected by the crushing method under a stereomicroscope. Among all 4977 examined gastropods, 55 individuals of two gastropod species, Gyraulus siamensis and Physella acuta, were found to be infected by T. unionis, with overall prevalence and mean intensity of infection of 1.11% and 16.65, respectively. The characteristics of the denticles indicated T. unionis as having moderately wide blades and moderately curved blade margins, with distinctive bend angles near the distal end. The quantitative characters showed some variations, which could be due to food availability. Molecular phylogenetic analysis conducted with 18S rRNA provided a monophyletic tree of our specimens and previously identified T. unionis, confirming species identification. This study represents the first record of T. unionis in Thailand.

Род Trollius L. (Ranunculaceae) во флоре Алтайской горной страны

Information on new characters, that were not previously used for the Trollius species identification is presented: consistence and degree of dissection of blade, type of margin, shape of teeth, number of petal veins, shape of nectarostigma, and morphological characters of fruits - type of the pericarp surface. The quantitative and qualitative morphological characters of the species are indicated: number of sepals and petals, distance from the petal base to the nectarostigma, length of the follicle and persistent style, as well as its shape and location. An identification key is proposed, which has been developed taking into account the suggested characters. A sinopsis of the genus Trollius (Ranunculaceae) of the Altai Mountain Country, including 3 species belonging to 2 sections is given. The synopsis includes nomenclature quotations, information on type specimens, distribution in the region, and general distribution for each species.